NYTimes- In a new twist, terrorists around the world are broadcasting their messages live during their deadly attacks, a New York police official told the Association for a Better New York on Wednesday.

Terrorists are streaming live video and pledging their allegiance to the Islamic State group as their attacks are unfolding, “a new phenomenon that we call ‘dying live,’” John J. Miller, the deputy police commissioner for intelligence and counterterrorism, said. Before, recorded videotapes were sent to television networks for later broadcast, he said.

Mr. Miller gave three examples. Last month in Magnanville, France, Larossi Abballa killed an off-duty police officer and the officer’s female companion. Mr. Abballa then videotaped himself live on Facebook, declaring his allegiance to the Islamic State, also known as ISIS or ISIL. Viewers watched as he debated the fate of the couple’s 3-year-old son, who sat terrified in the background. The police killed Mr. Abballa and rescued the boy.

In Orlando, Fla., the gunman who killed 49 people in a nightclub called 911 during an attack on June 12. “My name is I pledge of allegiance to Abu Bakr al-Baghdadi of the Islamic State,” he said to a dispatcher.

“He is throwing down that marker for ISIS, live during the incident, just the way he is told to,” Mr. Miller said.

“Again, he is streaming live, taking credit for ISIS,” Mr. Miller said. “So, what do we do about that?”

Mr. Miller spoke to the association at a breakfast, at the Roosevelt Hotel in Manhattan, to discuss the most recent trends in terrorism.

New York is a theme in many videos produced by the Islamic State, Mr. Miller said as he played one that showed a suicide bomber and then switched to a city scene.

“We need to know what is the bad guy’s plan, what was their target, how did they execute that plan, and most importantly if you took that plan and put it over a New York overlay, how are we protected here,” Mr. Miller said. He added that New York police officers are stationed in 13 locations around the world.

“New York remains statistically the No. 1 target for terrorists,” he said. “No other place has been the target of over 20 plots.”

“There is no new threat in that we have seen some version of every one of these before,” Mr. Miller said. “But what we haven’t seen is this type of cadence. What we haven’t seen is these threats coming as fast, as furiously, in such great numbers and with such regularity.”

Nearly 2,000 people in the department are trained and equipped for the emerging global threat, he said.

“We have a threat that is constantly morphing,” Mr. Miller said. “So no one plan can stay in place and work. You have to morph and change and develop, and in our case, grow.”

One attendee, Armenia Bell, 20, of Harlem, who is studying criminal justice at Berkeley College, said she was terrified by the Islamic State’s ability to attract followers solely through its propaganda.

“They have learned to network with people, to connect with people,” Ms. Bell said. “I think that’s the scariest thing I have ever heard in my life.”